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Educate Me on Thermostats

MrMarty51

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Miles City, Montana
When testing thermostats I hang them from a string that is threaded between the valve and the body.
When the T-Stat begins to open and fall off I then check the temp of the water.
One thing that I dont know is, is the T-Stat suppose to be full open at the temp that is stamped on the stat, or partially open or just beginning to open ?
That is the question. 🤷‍♂️😹😹😹
 
Yuppers- Starts to open.
And good job knowing to not let the thermostat sit on the bottom of the pan absorbing heat through contact directly. A big mistake many people make. Get the water close to temp and hold stat from edge with needle nose pliers is another option.

Keep in mind 1% off is acceptable by design error. For easy math- a 200 could start to open at 198 or 202 and is ok. Fully open should happen by 2% latest above opening temperature. So a 200 stat can begin opening at 202, fully open by 206 passes the test. It also could start at 198 and be fully open as soon as 200 and pass the test. So it’s easy to see the confusion. My instructor taught it like this- a thermostat does not control a nuke bomb- so it doesn’t have to be that precise. Want precision- be a nuke bomb mechanic. Haha

So 6.5 with 195 means almost 197 starts opening is ok. So it won’t be 100% open- that means maybe 200f it is 100% open. In the land of hot dry climates and big hills to climb - thats why I don’t like 195. Cruising at 194, flat road stat closed. Up the hill, pour on the coals and engine jumps heat near instantly. At 200 the stat is finally fully open and rushed how water to radiator where it goes all the way through the radiator before the air coming out the radiator Finally heats up the dissimilar metals of the fan clutch and it begins closing its valve to engage fan. By now that hot water is back in the engine as the fan is fully on. Stat stays wide open a long time trying to play catch up.

Hence fan clutch mod and other stuff trying to help.

Me in hot and dry climates (humidity adds great factor to radiator cooling before fan comes on) I decided long ago 180 stat is my friend. Yeah i loose a couple points in the mpg game- but it takes a lot of gallons diesel fuel to equal an engine swap! Haha
 
The stats that are now in the crossover I think might be 195s. It was a Sunday and I went to Oriellys to get the stats. I was surprised when I seen the made in Israel stamp on them, rather than made in chinesium.
I’ll get them popped out of there and see for sure what the heat range is.
If they are 195s I will be replacing them with 190s.
 
I tested the two 190* stats that I took out after the head gasket blew and the two new 180’s that I put in when I was putting it back together.

All 4 of them took 7* to go from closed to fully open. I wrote the temps down and put them in the 180* t stat box. I’ll find them and post them.

If I remember right they were about 1/2 way open at the rated temp when I did them.
 
I tested the two 190* stats that I took out after the head gasket blew and the two new 180’s that I put in when I was putting it back together.

All 4 of them took 7* to go from closed to fully open. I wrote the temps down and put them in the 180* t stat box. I’ll find them and post them.

If I remember right they were about 1/2 way open at the rated temp when I did them.

If they are that consistent- sound ls like that how the manufacturer made them. The numbers i said were from a class I had many moons ago. Could be it was a different manufacturer specs. I can’t remember what outfit put on that class.
What manufacturer were this stats?
 
I can’t remember what brand I bought right now. I do remember that they happened to be the same brand as I took out when I replaced them. We are at the beach but I’ll find the box when we get home and post a picture of it and the paper that I wrote the temps on.
 
I can’t remember what brand I bought right now. I do remember that they happened to be the same brand as I took out when I replaced them. We are at the beach but I’ll find the box when we get home and post a picture of it and the paper that I wrote the temps on.
You in the sand box. or?
 
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We came to Edisto Beech in South Carolina. Its my daddy’s side of the family and there is 15 of us. We have enjoyed the beech but me and my uncle and 3 cousins have been enjoying the fishing to. We have been fishing 32 miles off shore on a man made reef. The fishing has been excellent. We were able to keep over 60 fish in 2 trips out there. I can’t get the pictures of the rest of the fish on the other side of the picnic table to load.

My cousin has a 19 1/2’ center console boat with a 150 horse on it. The 3rd picture shows a Amberjack that I caught. The 4th picture is my little cousin holding one of the fish that he caught. The 5th picture is me holding a Barracuda that I caught and the 6th is another Barracuda that my little cousin caught. I don’t remember what the fish is in the 7th picture that I caught. And then a little Eel that we caught.
 
To be honest, I don’t know what he had in the boat. I hope that he has what we need if there was a emergency because there ain’t no phone reception after about 5 miles or so off shore.
Get a sat phone. Most of those are good for an XXX amount of free text messages, dont cost until a call is made.
At least then if You is in an emergency situation You can call and get help. You location can, within a degree or two be pinpointed too.
 
I would like to install 185 stats in the truck, but, there is no such a thing available for the 6.5.
I got on RA and ordered the 190s
 
Yeah, I thought about 180s, figured I’d try the 190s first and see how they do in the hot summer days. If I can get it all back together in time.😹😹😹🤷‍♂️
If it still runs what I think is too warm, then I think I’m going to do away with the NAPA coolant pump and install a Delco, then see what that does.
 
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